Neck pillow



FIG. 1 is a front perspective view of a neck pillow;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom side view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a right side view thereof.

The dotted lines in FIGS. 1-7 represent portions of the design that form no part of the claimed design. 

CLAIM The ornamental design for a neck pillow, as shown and described. 